Yamaha YZF-R1 1998, Service Manual

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ELEC
SELF-DIAGNOSIS
EB812000
SELF-DIAGNOSIS
The YZF-R1 features a self-diagnosing system for the following circuit(-s):
• throttle position sensor
• EXUP
• fuel level indicator light
If any of these circuits are defective, their respective condition codes will be displayed on the
tachometer when the main switch is set to “ON” (irrespective of whether the engine is run-
ning or not)
Tachometer display sequence
Circuit Defect(-s) System response Condition code
Throttle posi-
tion sensor • Disconnected
• Short-circuit
• Locked • The ignitor unit stays set to the
wide-open throttle ignition tim-
ing. The motorcycle can be rid-
den.
• The tachometer displays the
condition code.
3,000 r/min
EXUP • Improper connec-
tion
• Short-circuit
• The EXUP valve stays in the
open position for three seconds
and then the servomotor shuts
off. The motorcycle can be rid-
den.
• The tachometer displays the
condition code.
7,000 r/min
• Servomotor is
locked.
• The servomotor’s power supply
is constantly interrupted so that
it will not burn out. The motorcy-
cle can be ridden.
• The tachometer displays the
condition code.
Fuel level indi-
cator light • Improper connec-
tion
• The tachometer displays the
condition code.
8,000 r/min
When more than one item is being monitored, the tachometer needle displays the condition
codes in ascending order, cycling through the sequence repeatedly.
If the engine is stopped, the engine speed
3 is 0 r/min.